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Megumi’s going to kill Sukuna.
With a white knuckled grip on his pen Megumi takes deep breaths in through his nose, entire body strung tight. His other hand grips the fabric of his pants, almost threatening to tear it from his very skin.
It takes everything within him to bury the noises begging to be set free and even more not to squirm in his seat. He can’t even remember why he agreed to this in the first place and right now, he regrets ever giving in to Sukuna’s request.
He should’ve known nothing good would’ve come from today the moment Sukuna appeared in the doorway to his bedroom before Megumi’s alarm had a chance to go off. “I bought you something,” Sukuna purrs, hands tucked behind his back as he creeps into Megumi’s room and closes the door.
“No,” Megumi says.
“You don’t even know what it is.”
Megumi narrows his eyes and glares at his younger brother and the shit eating grin crawling up his face. It was difficult for a lot of people to believe they were related and if Megumi hadn’t grown up with Sukuna he wouldn’t have believed it either. The only similarity they seemed to share in genetics was dark hair that Sukuna dyed an ungodly pink. “Don’t care. It’s too early for this shit.”
“Onii-chan,” Sukuna whines, taking one step closer towards the bed and Megumi screws his fingers into the sheets. He hates it when Sukuna says that. Hates the way his voice drops an octave and his eyes roam Megumi’s body freely. And he hates the way it makes Megumi’s stomach flip. “Please?”
Megumi throws a wary look to his bedroom door and glances at the clock. Their parents wouldn’t come looking for them for at least twenty more minutes. But still. He flicks green eyes to Sukuna’s red and glares harder. “Five minutes.”
Those two words light Sukuna’s face up and he strides the rest of the way to the bed, tearing the sheets away from Megumi the moment it’s within reach. “That’s all I need.”
“Hey!”
Sukuna’s already climbing onto the bed, knees either side of Megumi’s thighs, an unmarked box dropping onto the mattress beside them. His smile is never wavering as he cups Megumi’s face in one hand and stills him in an instant. “Trust me? Big brother?”
Megumi huffs a breath between pouting lips. “You’ve got four minutes, little brother .”
The light shimmers in Sukuna’s eyes and he surges forward, immediately capturing Megumi’s lips in a kiss. Megumi closes his eyes, the tension in his shoulders melting away as Sukuna deepens the kiss, curling his tongue into his mouth. No matter how many times they kiss, how much spit they swap or how much Sukuna palms at him, Megumi’s cheeks never fail to burn from the simple fact he was kissing his brother and loving it. It made him ache in ways other boyfriends had never managed to. Made him wetter than anyone who had ever tried.
It was wrong.
But as Sukuna slides a hand over Megumi’s chest, down his front, and cups his mound through his sleep shorts, Megumi doesn't care. It was bliss. Heaven. Delicious. He whines as Sukuna rubs at his shorts, soaking the fabric in his slick and Megumi shakes his head, breaking the kiss when Sukuna pushes against the fabric. “No.”
Sukuna snorts. “I don’t wanna fuck you, not yet.”
The words burn more heat into Megumi’s skin and he lets Sukuna lay him down. Lets Sukuna ease his nerves with kiss after kiss, fingers reaching down to push Megumi’s shorts and underwear to one side so he can stroke Megumi cunt in earnest. Two fingers easily slide through the slick and Megumi’s breath hitches when Sukuna presses against his clit. “Kuna,” he gasps.
He hums, tugs Megumi’s bottom lip between his teeth, and circles his entrance with two fingers. “My blessing,” Sukuna whispers and he pulls his hand away. His lips continue to work against Megumi’s mouth and Megumi hears the rattle of the box. He cracks his eyes open, trying to look across to it, but Sukuna tuts. “Don’t spoil the surprise.”
Megumi nips at Sukuna’s mouth. “I don’t like surprises.”
“You’ll like this one.” Sukuna’s already reaching between them and he presses a quick kiss to the corner of Megumi’s mouth. “Trust me,” he says and Megumi closes his eyes, letting the sensations roll through him. There’s a warm weight across his lips as they kiss again and eventually there’s a pressure against his cunt. Megumi cracks his eyes open as Sukuna pushes whatever he has in his hands against Megumi again. “Trust me,” Sukuna repeats and he digs the pad of his thumb against Megumi’s clit, making him groan and hiss, muscles tensing before he relaxes.
And Sukuna pushes.
Megumi’s body opens for him, slick walls inviting him in and when it finally settles within him, Megumi moans. It’s weighty and thick and when he clenches around it his entire body flushes with heat.
“Wear this for me,” Sukuna whispers, nipping at Megumi’s mouth.
“Until when?”
Sukuna hums, one hand splayed over Megumi’s stomach, pressing just enough to make Megumi shiver from the pressure of being full. “Lunch. I’ll take it out at lunch.”
A groan rumbles through Megumi but as he clenches experimentally around whatever it is, he nods. “Okay.”
The first instant of regret hit Megumi during his first class when all of a sudden vibrations started to burn at his core and realisation hit him with exactly what it was Sukuna was asking him to wear. Megumi curses at his past self for agreeing to this without asking more questions, without thinking this through. And he curses at Sukuna as the vibrations come and go.
Second class has Megumi crossing his feet at his ankles and pressing his thighs together, hoping it would help quell the building tension growing inside of him. But it only makes it worse and Megumi forces himself to keep his legs spread, toes curled in his shoes, hips begging to rock and grind against the weight that presses everywhere inside of him.
Sometimes the vibrations stop, letting Megumi breathe, but when they come back he almost jumps from his seat and it’s a miracle nobody’s asking him if he’s okay.
Third class is just as tortuous as the other two and Megumi spends the last ten minutes ignoring whatever the teacher is saying. His eyes are glued to the clock counting down to lunch and to the moment his suffering will end.
Five minutes.
Four.
Three.
Two.
One.
The bell rings and Megumi hastily throws his stuff into his bag. His knees tremble as he stands and he doesn’t want to look at his seat, underwear already feeling thoroughly soaked. If he’s managed to drench his pants too he’s definitely murdering Sukuna.
He hurries through the door, taking a moment to collect himself when the vibrations start up again, more intense than ever before. Megumi grits his teeth, every step feeling like hell, his legs ready to give out on him, cunt throbbing and aching, desperate for release as he marches to their spot.
Past the science labs, past the music rooms. Take a left, a right, up the stairs that lead to the fire exit that doesn’t open and… Sukuna’s already there, bag hanging over two steps, phone gripped tightly in his hand, grin warming his face. “Onii-chan,” Sukuna says and Megumi sucks his bottom lip between his teeth with a glare, red dusting his cheeks. “You look beautiful.”
“Turn it off,” Megumi hisses through clenched teeth.
Sukuna pouts but he presses a button on his phone and Megumi sags against the wall in relief, his bag hitting the floor with a resounding thud. He focuses on breathing, on controlling the racing beat of his heart and the pounding in his cunt begging for more. Maybe he should go home. Convince the nurse he was sick and take care of himself.
When he looks back up at his brother, he knows Sukuna has other ideas and he steels himself as his baby brother stalks towards him. Sukuna presses a palm against the wall by Megumi’s head, his other palm reaching for the front of his pants. “You’re dripping,” Sukuna simply says, pride filling his voice.
Megumi huffs and he shoves a shoulder against Sukuna’s front. “You didn’t tell me that’s what it was.”
Megumi doesn’t get far as he tries to step away. Sukuna’s already pushing him back to the wall with his back to Sukuna’s front, cheek pressed against cool plaster. “You didn’t ask,” Sukuna whispers, breath tickling the shell of Megumi’s ear.
He didn’t. But that doesn’t mean Sukuna’s in the right and Megumi only huffs again, brows drawn into a glare. “You’re an ass.”
Sukuna chuckles and he brushes his nose up the nape of Megumi’s neck. “And here I thought you wanted me to take it out.”
“I do.”
“Say please.”
“Kuna!”
Sukuna laughs and he hooks his fingers in the bands of Megumi pants and underwear, shoving them down just enough to expose Megumi to the cool air. Shame washes through him as the scent of his sex fills the air. It was a good job nobody ever frequented this side of the school and Megumi hopes it stays that way as Sukuna reaches down and casually rubs two fingers over Megumi’s swollen sex.
It’s almost enough to make him cum there and then, knees quivering with a desperate need. He whines when Sukuna presses against his engorged clit and gasps when Sukuna dares to slide one finger between his damp folds and into his muscles. He nudges against the toy he settled there earlier and Megumi keens.
“You want it out?” Sukuna whispers.
“Yes,” Megumi gasps.
Sukuna removes his fingers and lays his palm against Megumi’s stomach. “Push.”
“Wha–”
“Push, Onii-chan.”
Megumi whines. Whatever brain cells he has are long destroyed by the need rolling through him and he clenches around the toy, gasping as he focuses on pushing it out. His muscles ache and shiver and he whimpers as the toy stretches him open achingly slow, so slow Megumi takes a moment to collect himself. His little reverie is short-lived when Sukuna presses against his stomach and Megumi’s muscles hitch. He keens, rocks on the balls of his feet, pushes with his muscles and…
And…
He groans as something falls out of him and hits the floor with a thud. Whimpers as slick drips down the insides of his thighs and whines as hears drops drip onto his pants. Megumi sucks in deep breaths, the muscles of his cunt clenching around what used to be there and he feels too empty now.
The heat of Sukuna’s body disappears for a moment as he picks up whatever it was and then he’s back, lips brushing the back of Megumi’s neck. He reaches Megumi's front with one hand and easily slides his fingers through the fresh collection of slick, moaning Megumi’s name against his skin.
“Can I?” he whispers, rubbing his clothed erection against Megumi’s ass.
Megumi involuntarily clenches and he nods before he can change his mind. “Ma– make it quick.”
Sukuna moans and Megumi hears the hurried unzipping of pants. “Yes, brother. You’re the best, brother. Fuck, fuck.” It’s only a matter of moments before the head of Sukuna’s cock brushes along Megumi’s cunt and catches Megumi's hole. “Oh, fuck ,” Sukuna mumbles and without another word or warning, he thrusts into Megumi in one sharp thrust. It knocks the air from Megumi’s lungs and he arches, chest pressed against the wall.
“Shit,” Megumi hisses, muscles tightening around Sukuna.
“So wet,” Sukuna whispers, “and warm and soft. Fuck. Onii-chan, onii-chan, onii-chan.” Sukuna moans in his ear, a litany of praises as he repeats those words and Megumi holds on. White hot noise fills his head as Sukuna carves a familiar space inside of him. “Onii-chan, onii-chan, onii-chan.”
“Ku- na ,” Megumi gasps and he rocks his hips back into each thrust. Meets every drag of Sukuna’s cock with a grind of his hips.
It takes no time at all for Megumi to cum. The wire thin tension he’s been strung on all day finally snaps and he fucks back, slamming himself down the length of Sukuna’s cock as he spasms around the length, more slick dripping down his thighs.
And it’s only a few moments later as Sukuna grinds into him, hips stuttering away, before Sukuna cums too, filling Megumi up until that mixes with his own slick and coats his thighs too.
“Fuck,” Megumi mutters and it seems forever until his brain starts working again.
Behind him Sukuna sucks in deep breaths, a mantra of “Onii-chan,” still on his tongue, lips pressing soft kisses against Megumi’s neck, hands soothing warm brushes up his side.
“Kuna,” Megumi whispers.
His baby brother hums and wraps his arms around Megumi’s waist. “I brought you a change of clothes.” Megumi nods and closes his eyes, letting his head rest against the cool plaster. “Onii-chan?” Sukuna whispers, so sweet, so innocent Megumi could almost believe it wasn’t Sukuna who just came in him. “Can we do this again?”
Heat blossoms across Megumi’s skin as he thinks about the best orgasm he’s had in a long time. Sure, it had been hell to deal with, but his body was feeling light and tingles in all the right places. It was the best he’s felt getting off in a long time and he almost feels defeated as he eventually says, “Fine.”